Militant Group Declares Statehood, Demands Allegiance From Other Organizations

BAGHDAD—The Sunni Islamist militant group whose three-week blitz through northern Iraq has nearly upended the country's fragile unity announced itself as a new Islamist "caliphate" on Sunday, unilaterally declaring statehood and demanding allegiance from other Islamist groups.

The announcement, recited in Arabic on the first day of the Muslim holy month of Ramadan by spokesman Abu Mohammed Al Adnani into an audio file,...